The present invention relates in general to boilers and, in particular, to a new and useful arrangement for fixing the spacing between tubes in a superheater or reheater section or in other parts of a boiler where the tubes extend through the volume of the boiler.
Superheater and reheater sections of boilers have side-to-side ties to maintain spacing. As illustrated in FIG. 1, there have been several designs that utilize a metal bar 10, strung between the superheater or reheater tubes 12 of each section. The means by which the metal bar 10 has been attached to the tubes 12 has varied, but usually involves a strap 14 as illustrated in FIG. 1 around the tube 12 or a lug 16 as illustrated in FIG. 2 welded to the tubes 12. These attachments to the tubes 12 require welding behind the spacer bar 18 shown in FIG. 2, which is difficult. The lugs 16 sit in grooves at the bottom of bar 18 and are held in the grooves by retainers 20.